Interchangeable continuous casting apparatus



Sept. 20, 1966 J. l. GREENBERGER INTERCHANGEABLE CONTINUOUS CASTINGAPPARATUS 5 Sheets-Sheet 1 Filed Sept. 19, 1965 HIS ATTORNEY Sept. 20,1966 J. 1. GREENBERGER INTERCHANGEABLE CONTINUOUS CASTING APPARATUSFiled Sept. 19, 1965 5 Sheets-Sheet 2 IN VEN TOR JOSEPH I. GREENBERGER jQ. 77x23;

HlS ATTORNEY Sept 1966 J. 1. GREENBERGER 3,273,208

INTERCHANGEABLE CONTINUOUS CASTING APPARATUS Filed Sept. l9 1965 5Sheets-Sheet 5 INVENTOR. JOSEPH l. GREENBERGER HIS ATTORNEY v UnitedStates Patent 3,273,208 INTERCHANGEABLE CONTINUOUS CASTING APPARATUSJoseph I. Greenberger, Pittsburgh, Pa., assignor to United Engineeringand Foundry Company, Pittsburgh, Pa., a

corporation of Pennsylvania Filed Sept. 19, 1963, Ser. No. 310,019 13Claims. (Cl. 2257.2)

This invention relates to the continuous casting of metallic workpiecesand, more particularly, to a continuous casting plant designed to assuremaximum production and capable of operating uninterruptedly forrelatively long periods.

It is a well-known fact that for a number of reasons in operatingpresent-day continuous casting plants considerable and frequentunproductive periods of time are experienced. One of the primary reasonsfor this loss in productivity has reference to the fact that processespresently employed require a discontinuance of the cast ing operationafter the metal in the ladle has been completely poured, until the emptyladle can be removed from the casting position, the dummy bar systeminserted and a second ladle, full of molten metal, positioned in itsplace. In some continuous casting plants, the time necessary to performthe changing of the ladles and preparing for the next casting cycleequals the time it takes to pour the metal from a ladle. This means thatthe production efiiciency of such a plant is about 50% and usually less.

Other production delays are caused by the time needed to effect achanging of used tundishes, worn molds and/ or replacement secondarycooling units as well as for changes incident to the change of the sizeand/or shape of the cast product. According to present general practice,it has been found that replacement of the tundishes is necessary afterevery casting cycle. With respect to mold maintenance, a mold may remainproductive for as many as several hundred casts. However, in comparisonwith ladle changes, the time necessary to change the tundishes, moldsand secondary cooling units is considerably longer, particularly incasting plants employing multiple strands.

It is an object of the present invention to provide a continuous castingplant wherein the ladles can be so changed as to assure more continuousoperation of the plant and wherein in no event will ladle changing delayoperation of the plant.

It is another object of the present invention to provide an arrangementfor quickly changing the tundishes, molds and secondary cooling units ofa continuous casting plant whereby the discontinuation of the operationof the plant incident to such changing will be reduced considerably.

It is a further object of the present invention to provide a structurefor supporting a number of ladles provided for a common tun-dish,including means for quickly positioning the ladles successively inoperative relationship with the tundish, wherein in moving one ladle outof the pouring position a second or replacement ladle will beautomatically positioned in the pouring position.

It is further contemplated by the invention to provide a similarconstruction for removing molds provided for a common strand from anoperative position to an inoperative position and repositioning a secondmold unit into the operative position.

It will thus be seen from the following description that by providing aconstruction whereby the ladles can be shifted without interrupting thecontinuous operation of the casting plant maximum production,particularly of high tonnage workpieces, can be realized together with agreater yield, since scrap losses incident to cutting off portions fromthe head and tail portions of the total cast will be reduced. Anotherinherent advantage in the extended uninterrupted operation of the plantis that greater slab uniformity in dimension and quality will be assuredand higher production efficiencies will be obtained.

With respect to the construction which enables the tundishes, molds andsecondary cooling unit to be quickly replaced, not only is there adefinite advantage in reducing production losses .incident to theoccasion when these elements require changing and/ or replacement, butof equal significance is the advantage that replacement elementsdesigned to cast a different size workpiece can be set up in readinessfor quick insertion into casting position with a minimum amount ofdelay.

These features and advantages as well as others will become more evidentwhen the following description is read along with the accompanyingdrawings of which:

FIGURE 1 is a schematic elevational view of the upper portion of acontinuous .casting plant, illustrating a system of ladles, tundishesand molds constructed in accordance with the present invention;

FIGURE 2 is a schematic and elevational view of the plant illustrated inFIGURE 1;

FIGURE 3 is a plan View, in smaller proportion, of the plantillustrate-d in FIGURES 1 and 2; and

FIGURE 4 is a modification, in certain respects, of the equipmentillustrated in FIGURE 3.

With reference, first to FIGURES 1 and 2, there is illustrated a ladlesupporting arrangement consisting of a number of spaced-apart columns.11, the lower end of which is secured to a substructure 12, the columnsserving to support at their upper portions parallel extending rails 13which are made of a length sufficient to handle three separate ladlecars, two at a time, such as, cars 14 and 15, illustrated in FIGURE 1.The ladle cars, as shown best in FIGURE 1, include two pairs of wheels16 which pass along the rails 13, the wheels of one pair being drivenindividually by separate motors 17. The ladle cars carry portable ladles18 having pouring open: ings 19 at their lower ends through which themetal is discharged and may be selectively interrupted by means ofstoppers 21. Each ladle car is also provided with a locking arrangement,which is shown only in FIGURE 2, consisting of a piston cylinderassembly 22 carried by one of the columns M, the piston of which isadapted to pass into an arm 23 formed at one end of the bottom of thecar which has an opening for receiving the end of the piston.

By this construction and in again referring to FIG URE 1, after themolten metal has been poured from the ladle 18 on the ladle car 14, thestopper 21 can be lowered into the opening 19 and the motors 17 operatedto move the ladle car 14 toward the left to a phantom position where itwill come to rest against a stop 20. Of course, if the ladle car 15 islocated on the left of the ladle car 14, as one views FIGURE 1, the car14 will move toward the right. Prior thereto, the ladle -1-8 for the car15 can be placed on the car 15 by a crane in readiness to take the placeof the ladle 18 of the car 14. Once the car 14 has been removed from itspouring position, the car 15 can be brought into this position in whichconnection the piston cylinder assembly 2 2 of the locking device willbe operated to correctly position the car in its pouring position. Oncethis occurs, the stopper 21 of the car 15 can be raised allowing themolten metal to issue therefrom. The time involved in shifting the emptyladle and replacing it with a full ladle will be less than the timerequired to empty the tundish, so that continuity of pouring will bemaintained.

With reference again to FIGURE 2, it will be noted that at the inside ofthe bases of the columns 11 opposed feet 24 are provided, the uppersurfaces of which serve to support a pair of beams 25 which run parallelto the rails 13 and, as in the case of the rails 13, are sufficientlylong to carry three tundish cars, two at a time. The beams 25 serve asrails for tundish cars 26 and 27 which are similar in construction tothe ladle cars 14 and being provided with two pairs of wheels 28, thewheels of one pair being driven by individual motors 29 shown both inFIGURES 1 and 2. The tundish cars may be maintained in their operativeposition by the brakes of the motors 29.

The tundish cars carry tundishes 33 which have the usual stoppers 34,the lower ends of which are inserted into nozzles 35 located at thebottom of the tundishes 33 when it is desired to prevent the metal fromflowing out of the nozzles. Prior to discontinuing the operation of thecontinuous casting machine to change the tundish 33 of the tundish car26, a new or rebuilt tundish 33 and car 27 is positioned on the tracks25 and preheated preliminary. to being inserted into the pouringposition. This preheating is accomplished in the instant case by fuelheating devices 36 which, as shown in FIGURE 1, are located on eitherside of the pouring position of the casting machine. The devices includetrunnion-mounted heads 37 to which there are connected fuel nozzles 38that may be positioned above and inserted into the covers of thetundishes. In order to obtain effective preheating, as shown in FIGURE1, the tundishes are provided with removable covers 40 which are usedduring the preheating period. When it is desired to change the tundish33 of the car 26, its motors 29 will be operated to advance the careither to the left or right depending upon whether the replacementtundish is at the left or right as one views FIGURE 1. Assuming thereplacement tundish car is in the position shown in FIGURE 1, then thetundish car 26 will be advanced to the left as one views FIGURE 1 andcome against stops 58. Immediately after this has occurred and after thehead 37 of the employed heating device 36 has been raised and rotated,so that the cover 40 can be removed, the tundish car 27 is advanced bythe operation of its motors 29 and when in the pouring position will bemaintained there by the brakes of the motors 29.

With reference now to the equipment provided for changing the mold,reference will be made first to FIG- URE 2. In this respect there isprovided a U-shaped supporting platform 41, shown best in FIGURES 3 and4, which serves to support a mold 42, the mold being connected to theplatform by a series of bolts 43. The platform is adapted to beoscillated by an oscillating mechanism 44 which is connected to andcarried by the structure of the casting machine. The bottom of the moldis provided with two pair of freely rotatable wheels 45 which areengaged by parallelly arranged rails 46 arranged directly below the moldon either side thereof. The rails are supported by structural members 47through pivotally connected links 48 which allow the rails 46 to beraised and lowered toward and away from the wheels 45 of the mold. Atone end of the rails there is connected thereto a piston cylinderassembly 51 which is also carried by one of the structural members 47through which means the rails are raised and lowered. FIG- URES 1 and 2show the rails in their lower-most positions out of contact with thewheels of the mold 42.

With respect to the construction of the supporting platform 41 and themold 42 reference at this point is made to FIGURE 3, whereit will beseen that over the platform is a U-shaped plate 52 wherein the open sideof the platform 41 is so arranged that the mold 42, including the plate52, can pass over and through the open side and away from the platform41. As previously indicated, the mold is normally secured to theplatform 41 by bolts 43 which pass through the plate 52 and whichreceive at their upper ends wedges which can be quickly removed 4 fromthe bolts to free the plate 52 and, hence, the mold 42 for longitudinalmovement.

As shown in FIGURE 2, to the left of the rails 46, there is provided amold-shifting system which is made up of a supporting beam 55 forsupporting a pair of parallel extending beams 56 that serve as guideways for a shiftable car 57 which is supported and guided on the beams56. The beams 56, as noted in FIGURE 2, are arranged at right angleswith respect to the rails 46. As best shown in FIGURE 3, themold-shifting car 57 is provided with two pairs of rails 58 and 59 whichserve as extensions of the rail-s 46 when positioned in line with thecasting machine. In still referring to FIGURE 3, it will be observedthat the mold 43 can be pushed manually over the rails 46 onto the rails58 where the mold will come to rest against stops 61 shown in FIGURE 2.Once this occurs, the car 57 can be traversed so that the replacementmold 62 carried by the mold transfer car 5'7- can be positioned in linewith the rails 46. The car, as shown in FIGURE 3, is moved traverselythrough the agency of a piston cylinder assembly 63 which is connectedto one end of the car 57, the extent of movement being controlled bystops 60.

FIGURE 4, as previously noted, illustrates a second embodiment of themold-shifting system. As shown, in place of the longitudinal shiftablecar 57, a rotatable turntable 64 is provided having two pairs of tracks65 and 66 so arranged that on rotation of the turntable, one or theother of the pairs of tracks will line up with the rails 46. Theturntable 64 is provided with an internally formed gear 67 which mesheswith a pinion 68 connected to a motor 68a. In this case a replacementmold 69 is set upon the tracks 66. After the used mold 43 is movedmanually onto the turntable, as shown in phantom in FIGURE 4, theturntable will be rotated to place the replacement mold in the phantomposition after which it will be manually moved into the casting machine.

There remains one other element illustrated to be commented upon andthat has reference to the secondary cooling unit 71 which is shown inFIGURES 1 and 2. While for simplicity the illustration of the presentinvention has not shown in detail a mechanism for quickly removing thesecondary units 61 relative to the mold, it will be appreciated by thoseskilled in the art that this may very conveniently be done, therebygiving the attendant advantage of being able to considerably reducedowntime incident to changing the secondary unit.

Thus, it will be seen from the above that in providing a shiftablearrangement for the ladle cars whereby two or more cars can be handledat once, uninterrupted operation of the casting plant is assured as faras the changing of the ladles is concerned. Thus, the period ofuninterrupted operation is limited to the life of the tundish nozzles,mold or secondary cooling unit, primarily the former. In this respectthe present invention will considerably eliminate the time loss incidentto replacing these elements by providing a system whereby the usedelements can bequickly removed and immediately replaced by otherelements.

In accordance With the provisions of the patent statutes, I haveexplained the principle and operation of my invention and haveillustrated and described what I consider to represent the bestembodiment thereof. However, I desire to have it understood that withinthe scope of the appended claims, the invention may be practicedotherwise than as specifically illustrated and described.

I claim:

1. In combination with a continuous casting machine employing a ladleand a mold, said mold being vertically movable relative to said ladleduring operation of said machine,

a first means for supporting the mold in a pouring position,

a second means for supporting two molds in such a manner that the moldscan be selectively positioned in said pouring position when saidvertical movement of said mold is interrupted, and

means for bringing at least a part of the second supporting means into asupporting position with one of the molds when in the pouring positionwhen said vertical movement of said mold is interrupted, thereby toallow the transfer of a mold from a supporting position with said firstsupporting means to a supporting position with said second supportingmeans.

2. In combination with a continuous casting machine employing a ladle,mold and tundish,

means for supporting two ladles in such a manner that the ladlies can beselectively positioned in a common pouring position,

means for moving the ladles into and out of the pouring positions,

means for supporting two tundishes in such a manner that the tundishescan be selectively positioned in the pouring position,

means for moving the tundishes into and out of the pouring position,

means for supporting a mold in such a manner that the mold can be movedfrom a casting position to a position remote therefrom,

a mold transfer car located remote from the casting position of the moldfor supporting at least two molds, and

means for positioning the car so as to receive a mold from the castingmachine, and to position a second mold in position for insertion intothe casting machine.

3. In combination with a continuous casting machine,

according to claim 2, wherein,

wheels are secured to said mold,

rails engage with said wheels, and

means for moving said rails into and out of engagement with said wheelswhereby said mold in the casting position can be moved away from saidcasting position.

4. In combination with a continuous casting machine,

according to claim 2, wherein said mold in the casting position isdetachably connected to a mold-carrying means, and

said carrying means having an open side for permitting a mold, whendetached from said carrying means, to move away from said carryingmeans.

5. In combination with a continuous casting machine,

according to claim 4, including means connected to and for oscillatingsaid mold-carrying means, thereby to oscillate said mold during thecasting operation.

6. In combination with a continuous casting machine employing a ladleand a pair of molds,

means for supporting one of said molds belows the ladle so that it canbe moved ultimately into a pouring position for receipt of molten metaland to a position remote therefrom,

a mold transfer car located in said remote position having moldsupporting areas for supporting at least two molds in which said areasare positionable alternately relative to said supporting means, and

means for positioning said car so that one of its supporting areas willreceive one of the molds from the casting machine and said othersupporting area will position the other mold for movement into saidcasting machine.

7. In combination with a continuous casting machine employing a mold, apair of tundishes and a pair of ladles arranged in a superimposedrelationship,

means for supporting said ladles in such a manner that the ladles can beselectively positioned in a common pouring position above a tundish,

means for supporting the tundishes in such a manner that the tundishescan be selectively positioned in the common pouring position above themold,

means for moving the ladle into and out of the pouring position whereinthe ladle is changed so as to maintain a sufficient volume of moltenmetal in the tundish in the pouring position, whereby a continuous flowof metal from a tundish is assured during the interchange of an emptyladle for a full ladle,

a support structure -for the said ladle supporting means and saidtundish supporting means, the construction being such that said ladlesand tundishes are maintained in a spaced vertical superimposedrelationship and allowed to move unrestrictedly relative to each otherand in a direction normal to the axis of said support structure,

said tundish being arranged below one of the ladles and above the moldand being smaller than either of the ladles so that both ladles cannotbe simultaneously located in the pouring position over the tundish,

said tundish having a cover, and

an opening in said cover of relatively small size in comparison with thecover through which molten metal is fed from the ladle.

8. In combination with a continuous casting machine,

according to claim 7, including means for preventing the ladles frommoving when positioned in the pouring position.

9. In combination with a continuous casting machine employing a mold, apair of tundishes, and a pair of ladles arranged in a superimposedrelationship,

means for supporting said ladles in such a manner that the ladles can beselectively positioned in a common pouring position above a tundish,

means for supporting two tundishes in such a manner that the tundishescan be selectively positioned in the common pouring position above themold,

means for moving the ladles into and out of the pouring position whereinthe ladles are changed so as to maintain a suflicient volume of moltenmetal in one of the tundishes in the pouring position, whereby acontinuous flow of metal from said tundish is assured during theinterchange of an empty ladle for a full ladle, and

a support structure for the said ladle supporting means and said tundishsupporting means, the construction being such that said ladles andtundishes are maintained in a spaced vertical superimposed relationshipand allowed to move unrestrictedly relative to each other and in adirection normal to the axis of said support structure.

10. In combination with a continuous casting machine,

according to claim 9, including means for preventing the ladles frommoving when positioned in the pouring position, and

means for preventing the tundishes from moving when positioned in thepouring position.

11. In combination with a continuous casting machine,

according to claim 9, including tundish preheating means arranged toheat the tundish When in a position away from the pouring position.

12. In combination with a continuous casting machine, according to claim9, in which said means for supporting said ladles and tundishes aresufiiciently long to support three ladles and tundishes, whereby areplacement tundish and ladle can be positioned on either side of aladle and tundish in the pouring positions, and

tundish preheating means are arranged on both sides of said pouringposition to preheat a replacement tundish which may be located on eitherside thereof.

13. In combination with a continuous casting machine employing at leasta pair of molds, a pair of tundishes and a pair of ladles arranged in asuperimposed relationship,

means for supporting said ladles in such a manner that the ladles can beselectively positioned in a common pouring position above a tundish,

, means for supporting said tundishes in such a manner I means formoving the ladles into and out of the pouring position wherein theladles are changed so as to maintain a sufficient volume of molten metalin one of the tundishes in the pouring position, whereby a continuousflow of metal from said tundish is assured during the interchange of anempty ladle for a full ladle,

a mold transfer car located in a remote position for supporting at leasttwo molds, and

means for positioning the car so as to receive one of the molds from thecasting position and to position said other mold in position forinsertion'into the casting position.

References Cited by the Examiner UNITED STATES PATENTS 2,519,313 8/ 1950Haklin 22-82 2,732,601 1/ 1956 Junghans 2257.2 X 2,768,413 10/ 195 6Alexanderson 22-57.2 2,799,906 7/1957 Duncan 2275 I. SPENCER OVERHOLSER,Primary Examiner. R. S. ANNEAR, Assistant Examiner.

1. IN COMBINATION WITH A CONTINUOUS CASTING MACHINE EMPLOYING A LADLEAND A MOLD, SAID MOLD BEING VERTICALLY MOVABLE RELATIVE TO SAID LADLEDURING OPERATION OF SAID MACHINE, A FIRST MEANS FOR SUPPORTING THE MOLDIN A POURING POSITION, A SECOND MEANS FOR SUPPORTING TWO MOLDS IN SUCH AMANNER THAT THE MOLDS CAN BE SELECTIVELY POSITIONED IN SAID POURINGPOSITION WHEN SAID VERTICAL MOVEMENT OF SAID MOLD IS INTERRUPTED, ANDMEANS FOR BRINGING AT LEAST A PART OF THE SECOND SUPPORTING MEANS INTO ASUPPORTING POSITION WITH ONE OF THE MOLDS WHEN IN THE POURING POSITIONWHEN SAID VERTICAL MOVEMENT OF SAID MOLD IS INTERRUPTED, THEREBY TOALLOW THE TRANSFER OF A MOLD FROM A SUPPORTING POSITION WITH SAID FIRSTSUPPORTING MEANS TO A SUPPORTING POSITION WITH SAID SECOND SUPPORTINGMEANS.